POTENTIAL PARAMETERS FOR BINARY NOBLE-GAS MIXTURES FROM THERMAL-DIFFUSION MEASUREMENTS

The unlike interaction parameters (epsilon(12)/k, sigma(12)) are deter mined for nine binary inert gas mixtures from thermal diffusion measur ements assuming both Lennard-Jones (12-6) and Modified Buckingham Exp- 6 potentials. The experimental alpha(T) data are analysed by using two different modes of temperature dependence, namely, (i) alpha(T) = A - B/T, and (ii) alpha(T) = a + b/T-1/2 + c/T, where A, B, a, b, and c a re temperature-independent constants. It is found that the parameters obtained from the LJ (12-6) potential and assuming alpha(T) = A - B/T are more acceptable than those obtained from the Exp-6 potential. More over, the alpha(T) data are analysed according to a new potential mode l, namely, the Maitland-Smith n(($) over bar r)-6 potential, which giv es a remarkably good representation for the inert gas systems studied.